(1) Field
The present invention generally relates to the field of wireless communication, and particularly to a method for providing wireless communication between a first station and a second station as well as to a station for performing a wireless communication.
(2) Description of the Related Art
A commonly known type of wireless system makes use of high available bandwidth and small antenna size. Such a system, known as millimeter wave solution, allows for a high rate wireless data transmission e.g. beyond 1 Gbps.
A first known implementation of such a wireless system comprises a channel equalizer including linear, decision feedback or maximum likelihood sequence estimation (MLSE) equalizer. In case of a high data rate transmission, the symbol duration is correspondingly short such that the multipath channel delay spread may be much longer than the symbol duration. As a consequence, the equalizer becomes complex and needs a lot of processing power.
A further known solution uses the orthogonal frequency division multiplexing (OFDM) technique for resisting against multipath interference in wireless communications. This OFDM modulation has been already implemented e.g. for transmissions in wireless LAN systems. However, as an OFDM signal is the sum of a large number of subcarriers, it tends to have a high peak-to-average power ratio (PAPR). Because of the inherent linear modulation of the OFDM technique and because of the high peak-to-average power ratio issue, the overall power consumption of power amplifier is very high with respect to other multiplexing techniques. Another disadvantage is that the OFDM demodulation requires complex units for carrying out high-speed fast Fourier transform (FFT) and other signal processing.
A further solution is proposed by the European patent application 04 027 554 of Sony, which disclosure is herewith incorporated by reference. A pair or several pairs of sharp beam antennas are used for both the transmitting and the receiving side of a wireless communication, wherein each pair of sharp beam antennas can be steered to match the direction of its corresponding strong reflection path. Depending on the steering resolution, the strong reflection path can be matched and other reflection paths can be disregarded. This results in the channel delay spread being shortened. On the other hand, as very few communication paths or ideally only the strongest reflection path is received, the overall received power is drastically reduced. This drawback has to be compensated for by additional antenna gain obtained from the sharp beam antennas.
Accordingly, the known solutions suffer from the need of high-speed and complex signal processing circuits, as well as from high power consumption and non-optimum use of power transmission.